Technically he’s not wrong. It’s a gray area currently untested (AFAIK) in the court system. See this opinion from the Michigan Attorney General for more.

TL;DR:

It is my opinion, therefore, that a Michigan resident who holds a concealed pistol license issued by another state is exempt under subsection 12(1)(f), MCL 28.432(1)(f), of the Firearms Act from obtaining a license to purchase, carry, possess, or transport a pistol as required by section 2, MCL 28.422, but is not exempt from obtaining a concealed pistol license under section 5b, MCL 28.425b, of the Act, in order to carry a concealed pistol in Michigan.